Strain insulator



June, 24 .1924. D 1,498,622

W. T. GODDARD STRAIN INSULATOR Filed Oct. 25. 1919 2 Sheets-Sheet 1 June 24 1924. r 1,498,622

W. T. GODDARD STRAIN 'msum'ron Filed Oct. 25 1919 2 Shuts-Sheet 2 INVENTOR Wa iier T fi'vddani is ATTORNEY POIHCQCI out in the claims Patented June 24, 1924.

UNITED STATES PATENT OFFICE.

WALTER T. GODDARD, 0F HAMILTON, ONTARIO, CANADA, ASSIGNOR, BY MES'NE AS- SIGNMENTS, TO LOCKE INSULATOR COB/DURATION, OF BALTIMORE, MARYLAND,

A CORPORATION OF MARYLAND.

STRAIN INSULATOR.

Application filed October 25, 1919.

T 0 all 207mm 2'25 may concern:

Be it known that I, IVALTER T. Gonninu), of Hamilton, in the Province of Ontario and Dominion of Canada, have invented certain new and useful Improvements in Strain Insulators; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming a part of this specification, and to the reference numerals marked thereon.

My present invention relates to electrical appliances and more particularly to insulators having special reference to types of insulators used on high tension lines and referred to as strain insulators inasmuch as they are themselves large and heavy and are used to support heavy bodies and the invention has for its object to improve the connection between the insulator proper. usually consisting of a body of porcelain, and the metallic devices through which it is connected to the supporting or supported element. The in'iprovcments are directed in part toward providing a protective housing for the joint between the elements and also an arcing ring in Conjunction therewith. To these and other ends the invention resides in certain improvements and combina tions of parts all as will be hereinafter more fully described, the novel features being at the end of the specification.

In the drawings:

Figure l is a side view of a suspension insulator constructed in accordance with and illustrating one embodiment of my invention;

Figure 2 is an enlarged top view thereof;

Figure 3 is a longitudinal fragmentary section on the line 33 of Figure 2 Figure 4 is an enlarged fragmentary side view of the head of the frangible element and its connected element with the housing removed;

Figure 5 is a top view of the parts shown in Figure 4 but with the housing in place and shown in horizontal section, and

Figure 6 is a detail section on the line 66 of Figure 4.

Similar reference numerals throughout the several-views indicate'the same parts.

Serial No. 333,159.

I have illustrated my invention, in the present instance, embodied in a suspension straininsulator that is completely shown in Figure 1 the bod 1 portion of which. consists of the frangible silicious element or insulator proper indicated at 1. It is in. the form of an extended cylinder of solid porcelain and as both ends or heads thereof and associated parts are of the same construction, a description of one will suffice for both.

The head of the insulator element is reduced as shown at 2 in Figure I, and below the reduced portion is formed a shoulder 3. The reduced portion itself has openings 4: therein running from the exterior to a central cavity or well 5. On top of the reduced portion, as shown in Figures 3 and 5, is a metal ring 6 which ring is connected to the frangible element by a continuous flexible member 7 that is laced back and forth around the ring and through the apertures 4 in the manner and for the purposes e:-;- plained in my prior application, Serial Number 273,145, filed January 25, 1919. The flexible member or lacing preferably consists of a metal cable and after it is applied it is stretched to equalize and distribute the strains it imposes upon the frangible element by means of jack screws 8 threaded into the ring 6 and bearing against the head 2, as shown in Figure 6. This last mentioned feature, however, forms no part of the present invention but is fully described and claimed in my copending application Serial N o. 333,157, filed of even date herewith.

The insulator unit is hung from its support or attached to the member that it supports by the ring 9 of an eye bolt 10 and in the practice of my present invention, the enlargement 11 of this eye bolt is adapted to rock in a socket 12 formed by en'ibossing the crown of a bell shaped sheet metal housing 13 that is fitted over the head of the frangible element and its connected element 6. The lower edge 14 of the housing rests upon the shoulder 3 of the frangible element and just above this point of contact the sheet metal is doubled upon itself to form an annular outwardly projecting flange This flange constitutes an arcing ring that prevents'the lacing 7 from, being weakened or deleteriouslv aflected by possible arcs. The housing as a whole, from the point of entrance of the eyebolt 10 into its crown down to its point of contact with the porcelain, presents a succession of downward curves on its exterior surface that offer a complete rainshed, preventing the entrance of water, dust and other foreign substances into the joint or connection between the elements 1 and 6; I further preferably provide an inner partition 16 at the base of the socket 12, sealing it from the interior of the housing and preventing the entrance of water along the eyebolt 10 from continuing down to the insulator.

The flange 15, aside arcing ring, has another function.

from providing an It 15 compressible and gives resiliency to the engagement of the edge 1 1 of the housing with the shoulder 3, so that a perfectly tight joint is made and the connected parts are held taut against undue relative movement. To place the ring or flange under tension, I provide threaded posts or bolts 17 on the connected ring 6 that extend through apertures in the housing and are surmounted by nuts 18 that are tightened down against the housing to draw it down upon the insulator. When so tightened, it is held between the nuts and bosses 19 on the ring 6 in which bosses the posts 17 are anchored. These bosses limit the degree to which the resilient portion of the housing may be compressed.

An insulator constructed in accordance with my invention presents a neat appearance and an exterior surface that does not lend itself to the accumulation of foreign matter.

I claimas my invention:

1. In a strain insulator, the combination with a frangible element of insulating material and a connected element, of means for supporting one of said elements upon the other, said means comprising a continuous flexible member, of a housing for the connected element embodying a raised central portion, and an attaching element secured to such raised portion, said housing being spaced from a portion of said frangible element and from said flexible connecting element and being provided with an integral resilient portion for engaging another portion of said frangible element.

2. In a strain insulator, the combination with a frangible element of insulating material and a connected element, means for supporting one of said elements upon the other, said means comprising a continuous flexible lacing member, of a housing spaced from a portion of said frangible element and from said flexible element, said housing being adapted to engage another portion of said frangible element and having an integral flexible portion forming an annular rib element.

3. Ina strain insulator, the combination with a franglble element of lnsulating material and a connected element, means supporting one element by the other, of a resilient housing for the connected element having a resilient engagement with the frangible element.

4. In a strain insulator, the combination with a frangible element of insulating material and a connected element, means supporting one element by the other, of a resilient housing for the connected element having a resilient engagement with the frangible element and compression devices on the connected element cooperating with the housing to force it into such engage ment.

5.111 a strain insulator, the combination with a frangible element of insulating material and a connected element, means supporting one element by the other, of a resilient housing for the connected element having a resilient engagement with the frangible element and bolts on the connected element extending through the housing and provided with nuts cooperating with the lat-- ter to force it into such engagement.

6. In a strain insulator, the combination with a frangible element of insulating material and a connected element, means supporting one element by the other, of a sheet metal housing for' the connected element having a compressible annular rib near its junction with the frangible element adapted ion to serve as an arcing ring and compression 7 devices on the connected element cooperating with the housing to press the latter into resilient engagement with the frangible element. r

7. In a strain insulator, the combination with a frangible element of insulating material embodying a head having a shoulder,

and a connected element embodying a metal body overlying the head, means supporting oneelement by the other, of a housing embodying a bell shaped sheet metal covering for the connected element and the head of the frangible element, said housing having a raised central portion at its top and an annular compressible rib near its bottom adapted to serve as an arcing ring, an attaching element secured to the raisedportion of the housing, the latter presenting'a continuous rain shedding surface from the region of the attaching element to its junction with the frangible element, and compression devices on the connected element cooperating with the housing to force the edge thereof into resilient engagement with the shoulder on the head of the frangible WALTER T. GODDARD. 

